Investigating oral fluid and exhaled breath as alternative matrices for anti-doping testing: Analysis of 521 matched samples

Abstract

Current anti-doping testing is primarily conducted in urine and blood. Recently, due to confounding factors with urine and blood collections such as invasiveness, cost, and stringent shipping conditions, there has been a push for the use of alternative sample matrices to ameliorate these issues. Gaining support within the anti-doping field is the use of oral fluid, and more recently exhaled breath, as viable alternative or complementary matrices to traditional urine and blood for drug testing. Thus, we designed a first-in-field study with the purpose of investigating the utility of oral fluid and exhaled breath testing, and the preference of athlete participants, comparative to conventional anti-doping methods of urine testing. To accomplish this, 521 total matched samples, consisting of exhaled breath, oral fluid, and urine samples, were collected and analyzed, and the results compared across matrices. Participants in this study preferred the exhaled breath collection (rated 4.90 ± 0.34 out of 5, mean ± SD) over the oral fluid collection procedure (4.29 ± 0.85), and most preferred both over urine collections. Exhaled breath resulted in the shortest collection time (2.58 ± 1.00 min, mean ± SD), followed by urine (3.08 ± 1.50 min), and finally oral fluid (4.14 ± 1.94 min). Prohibited substances from the drug categories of stimulants, narcotics, cannabinoids, diuretics, glucocorticoids, beta-blockers, and others, were analyzed in this study for a comparison of testing efficacy. Of the total findings 49% were detectable in only urine, 38% in urine + oral fluid, and 9% in all three matrices. Of the unique findings 3% were detectable in only oral fluid, 1% in oral fluid + breath, and 0% of unique findings were present only in exhaled breath. The findings from this study provide a strong foundation for the future use of oral fluid and exhaled breath as viable alternative or complementary matrices for in-competition anti-doping testing.

Keywords: Anti-doping; Exhaled breath; Oral fluid; Urine.